Peanuts

Discovered by conquistadors in South America, peanuts are a product of the New World. But that doesn't mean they grow on trees. Goobers, which are legumes, are raised underground and pack a hearty serving of protein.

Walnuts

Walnuts are the oldest tree fruit—that's right, fruit—known to man. Traded along the Silk Road for centuries, the meaty kernels arrived in the U.S. in the late 1700s. One handful boasts more antioxidants than other shelled snacks.

Pistachios

Legend has it that pistachio trees were planted in Nebuchadnezzar's famed gardens around 600 BC. While the green morsels have a royal past, they're actually seeds loaded with vitamin B6 (20% of your daily value per ounce).

Almonds

Botanically speaking, almonds are also a fruit, which explains why they're so good in sweets—just think about macaroons. In addition to flavor, one ounce supplies the same amount of polyphenols (health-promoting compounds) as a cup of green tea.